HIROSHIMA, Japan — U.S. House Speaker Nancy Pelosi on Tuesday became the highest-ranking serving American official to pay respects at the memorial site of the world's first atomic bomb attack.

Democrat Pelosi is in Japan for a two-day gathering of top legislators from the Group of Eight industrialized countries.

On Tuesday morning, she and the other G-8 representatives visited Hiroshima's Peace Memorial Park before heading into an all-day meeting.

No sitting U.S. president or vice president has ever visited Hiroshima. As speaker of the House of Representatives, Pelosi is second in line to the presidency after U.S. Vice President Dick Cheney.

Former U.S. President Jimmy Carter stopped by the memorial in 1984, after his presidency, but he did not visit in any official capacity.

Paying respectsGenyu Izawa, a Buddhist priest, stood by as each of the G-8 officials laid flowers at the arch-shaped monument inside of which a stone chest holds the names of bomb victims.

"As a Japanese, I am grateful that they are thinking about this and have all gathered here, the site of the atomic bombing," said Izawa, who traveled from Tokyo to show his support to Pelosi for her longtime commitment to Tibet issues.

An estimated 140,000 people were killed instantly or died within a few months after an American B-29 bomber dropped its lethal payload on Aug. 6, 1945.

Three days later on Aug. 9, 1945, the United States dropped a nuclear bomb on the city of Nagasaki, killing about 80,000 people. Japan surrendered on Aug. 15, ending World War II.

Japan, which adopted a pacifist constitution after the war, has since become one of the staunchest opponents of nuclear proliferation.

Ban on nuclear weapons urgedAt a ceremony last month marking the 63rd anniversary of the bombing, Hiroshima Mayor Tadatoshi Akiba urged the next U.S. president to support a proposed ban on nuclear weapons. And Japan submitted a resolution in the United Nations last year calling for the abolition of nuclear weapons. Akiba said 170 nations supported it, with the United States. one of only three countries opposed.